Cam grinding machine



Oct. 22, 1935. A P STElNER ET AL' 2,017,927

GAM GRINDING MACHINE Filed Aug. 7, 1929 e sheets-sheet 1 Hnos P. srs-vsnEDGHR P. wir/l:y BY CoA/ann L. o'r-r Hav/101m s. Bumsen Oct. 22, 1935.

A. P. sTElNER ll=:r A1. 2,017,927

CAM GRINDING MACHINE 6 Sheets-Sheet 2 Filed Aug. 7, 1929 HHOS P. STEINEREDGHR P, WINE BY. ccm/RFID l... oT'r HnRoLJ: 3111.515541 W/ ATTORNEYS.

Oct. 22, 1935. A,`P STE|NER ET AL 2,017,927

CAM GRINDING MACHINE Filed Aug. '7,- 1929 e sheets-sheet INVENTORS #mo/sP. STE/NER Emana' P. wim:` BY CoA/Rm: 1 01'1- Oct. 22, 1935.'l A. P.sTElNl-:R Er AL 2,017,927

CAM GRINDING MACHINE Filed Aug. 7, 1929 6 Sheets-Sheet 4 INVENTUM HnosPA STE/NER E ncvnn n wuve co/vnnp l.. orT

oct. Y2z, 1935. A, P, STElNE-R -AL 2,017,927

CAM GRINDING MACHINE Filed Aug. 7, 1929 6 Sheets-Sheet 5 F-IS 6 HNOS R,STE/NER CONRHD L. OTT

6 Shets-Sheet 6 lA. P. sTElNER ET Al.

CAM GRINDING MACHINE Filed Aug. '7, 1929 Oct. 22, 1935.

Patented Oct.v 22, 1935 UNITED STATES FFICE CAM GRINDING MACHINEApplication August "I, 1929, Serial No. 384,068

32 Claims.

Our invention relates to machines for grinding cam shafts and the primeobject of the invention is to provide a machine which will operateautomatically to completely grind the cam shaft.

Further objects are to provide new and improved means for indexing thevarious mechanisms and timing the cycles of operation so as to preservethe synchronism of the mechanisms.

Further objects and advantages will become apparent as the descriptionproceeds.

Referring to the accompanying drawings, which are made a part hereof andon which similar reference characters indicate similar parts,

Figure 1 is a front elevation of the machine,

l5 Figure 2 is an end elevation looking from the left of Figure l,

Figure 3 is a plan view of the head stock with parts shown in section,

Figure 4 is an end elevation of the driving mechanism for shifting themaster cam roller,

Figure 5 is a front elevation of the parts shown in Figure 4,

Figure 6 is a' front elevation of the timing cam and the control valvewith the latter shown in section,

Figure 7 is a plan view of the timing cam and the control lever,

Figure 8 is a somewhat diagrammatic view of the wiring circuits andfluid conduits by means of which the various mechanisms arehydraulically driven.

In machines for grinding cam shafts as heretofore made the variousoperations of the machines were controlled by an operator so that it wasimpossible for one operator to run more than a single machine. With thismachine the operator places the work in position in the machine andstarts the machine, whereupon the entire cam shaft is ground to size andthe machine is automatically stopped when the cam shaft is finishedwithout any further attention on the part of the operator. 'Ihis enablesa single operator to run a number of machines at a considerable savingin expense.

In the drawings reference character I0 indicates the bed of the grindingmachine having a work carriage'll, a wheel base I2 in which is mounted agrinding wheel I3. A wheel I4 provides means for manually moving thegrinding Wheel toward and from the Work. 'I'he Work carriage Il isprovided with a head stock I5. The head stock is driven by a motor I6through a reduction unit I'I. The head stock and tail stock are mountedupon a swinging cradle or rock bar I8 which is suitably'pivoted upon thework carkmeans o'f a sprocket chain 38.

mounted on the outer end of the screw 22 by 40 riage so that the workmay have the necessary swinging movement toward and from the grindingwheel to grind the cams. The cradle I8 is pivoted at the right hand endthereof as viewed in Fig. 1 and in Fig. 2, the cradle is shown in 5 endview. Mounted in the head stock I5 is a master cam I9 which is axiallyaligned with the work, not shown, which work is carried between the headand tail stocks in the usual way. 'Ihe necessary swinging motion of thework carrying 10 cradle or rock bar is provided by the master cam whichis resiliently held against a follower roll 20. The roll 20 is mountedso as to move axially along a shaft 2l, its movement being produced by ymeans of a screw 22 and a bifurcated member 23 l5 which engages thesides of the cam roller 20 so that rotation of the screw 22 will movethe cam follower roll 20 to position it opposite the desired cam cn themaster cam shaft.

The means for shifting the roller 20 to its posi- 20 tions will now bedescribed: This mechanism consists of a rack 24 slidably mounted in thebed of the machine and attached to a piston rod 25 by means of a bracket26. 'Ihe piston rod 25 is connected to a piston 2-'I in a cylinder 28 25which piston and-cylinder form the motor for reciprocating the workcarriage. 'Ihe rack 24 engages a pinion 29 on a shaft 30 which ismounted in the bed of the machine. 'I'he inner end of the shaft 30carries a bevel gear 3I which 30 meshes with a corresponding bevel gear32 on a shaft 33. The bevel gear 32 is slidably mounted on the shaft 33so that the rack 24 and shaft 33 may move with the work carriage I I.The shaft 33 also carries a sprocket which drives alchain 35 .34- whichforms the driving connection with a sprocket 35. Another sprocket 36mounted to. rotate with sprocket 35 drives a sprocket 31 by Sprocket 31is means of which the cam follower roll 20 is moved along the shaft 2|.It will be seen from the construction just described that movement ofthe work carriage II to position the work axially of the grinding wheelwould also move the camlfol- 45 lower roll to position it opposite thevarious cams on the master cam shaft. The gearing connection between therack 24 and screw 22 is such that the cam follower roll is moved througha much shorter distance than the work Vcarriage moves. A spring 38 ismounted in a projection i 39 of the head stock cover. 'I'his spring isheld between two caps 40 and 4I on a pin 42 which is connected to a lug43 on the swinging cradle I8. 'I'he purpose of the spring 38 is to holdthe cam shaft |9 against the cam follower roll 20.'

A cylinder 44 is also secured to the cover 45 of the head stock. Thecylinder 44 carries a piston bolt 50 passes is slotted to provide alittle lost 10 motion lbetween the link 49 and piston rod l48. Thepurpose of the slot is to provide lost motion to allow free oscillationof the cradle duri-ng grinding operations. The inner end of the link 49is secured to a lug 5| on the swinging cradle l5 |8. The chambers on theopposite sides of the piston 41 are connected by pressure uid lines 52and 53. When pressure fluid is introduced into the cylinder 44 throughline 52 the cradle will be withdrawn to separate the master cam from thecam follower roll and also separate the work from the grinding wheel soas to allow the work to be traversed past the grinding wheel. ,The4

pipe 52 is provided with a ball check valve 52 around which there is aby-pass passage 58 so that the fluid may freely flow into the cylinder44 but will have its return ow checked so as to prevent too sudden areturn of the master cam shaft against the cam follower roll.Thisprevents injury to the master cams and to the cam follower roller.-

Tzming mechanism The timing mechanism will now be described:

ating a limit switch 56 which switch is in circuit with the work drivingmotor. The cam 54 is secured to cam 55 by screws 9 positioned througharcuate slots 8. These slots permit ad- 40 justment of cam 54 relativeto cam 55 to change the time at which the work drive motor is slowed Idown. The operation of the limit switch is as follows: The switch 56controlled by the cam 55 is normally closed. This closes a circuitthrough -lines 51, 58,' 59 and coil 69 to energize this coil and closeswitch at 6|; this closes a circuit through the lines 62, 63, 64,resistances 65, line 66, eld 61 and line 68. A circuit is also normallyclosed through line 62, 69, resistance 10, line 66, field s1 and une es.n win therefore be noticed that when the line 62, 69, etc. operates, thecircuit goes through resistance element 10. When theswitch 6|` is closedcurrent may also-pass through a resistance 65 which is in parallel with'the resistance'10 when the switch 6| is closed therefore the totalresistance between wire 62 and wire 66 is lessened so that a, greateramount of current may flow through the eld 61. When the switch 6| isopen the main motor runs at a certain speed. lWhen the switch 6| isclosed the current through the field coil is increased and the motorconsequently slows down to a speed suitable for finishing grinding.

'I'he hydraulic mechanism later to be described is controlled by meansof cam 54 on a shaft 1|. Shaft 1| is driven by a motor 12 throughreduction gearing 13. The cam 54 operates a lever 14 on which lever is acam follower 15 which is aml -engaged by a projection 16on cam 54. Thelever 14 is pivoted at 11 on the bed of the machine. On the end of thelever opposite the cam is an index finger 18 which engages in notches ina spacing bar 19 secured to the work carriage of "gfthe machine. Thenotches 88 in the spacing bar during grinding operations.

correspond to the spacing of the cams on the shaft which is to beground. A valve casing 8| is secured to the front of the base of themachine. This valve casing is bored to receive valves 82 and 83. Thevalve 82 is a reversing 5 valve which distributes the pressure uid tothe cradle retracting cylinder 44 and also to the wheel base cylinder8,4.' The valve consists of spaced disks which control valve ports 52and 53, 81, 88, 89 and 98. A piston rod 9| extends 10 up through thevalve casing and is engaged by the'end of the lever 14 by which thevalve is operated. A spring 92 is positioned beneath the lower disk onthe valve and rests at the lower end of the bore which forms the valvebody. This 15 spring tending normally to hold the valve disks inelevated position, as shown in Figs. 6 and 8. Pressure fluid is suppliedto the valves by means of a pump 93 delivering fluid through a line 90.When the valve 82 is in position shown in Fig- 20 ures 6 and 8 pressurefluid is delivered through the line 98, line 88 to the cylinder 84 tomove the wheel base to its forward or grinding position and hold itthere. With the Valve in the position just described fluid will passthrough the line 53 to the 25 cylinder 44 at the rear of the piston 41to hold the piston in its forward position so that the master cam may beengaged by the cam follower roller Lost motion is provided by -a slot 49in the link 4l), this allows free 80 swinging movement of the cradlewithout any interference from the piston 41. When the cam 54 has beenmoved so that the point 16 of the cam raises the point 15 of the lever14 the opposite end of the lever will be depressed so as to move the 35valve disks to close the ports 88 and 53 from the pressure line 98 andto open the lines 81 and 52 to pressure line 90. At the same time lines88 and 53 are connected with the exhaust line 89 so that fluid may nowpass from line 90 through 4o line 81 to the forward side of piston 86 toretract the grinding wheel from grinding position and pressure fluidwill pass through line 52 to the forward side of piston 41 to retractthis piston and to move the master cam from engage- 45 ment with the camroller 20 and likewise to move the work to rmit the grinding wheel toclear the cams as the Work carriage is traversed to move another caminto grinding position. It should be noted that the cam point 16 will 50rest upon the shoe 15 only for an instant. The lever 14 therefore wouldtend to drop down and to shift the valve to the position shown inFigures 6 and 8 before the necessary operations of indexing the workcould be completed. This 55' would occur but for the fact that thecontrol valve 83 is opened sufficiently just before contact 15 reachesthe top of cam 16 to allow the carriage to begin its traverse and sowhen the cam releases the lever the carriage has moved 60 far enough forthe spacing bar 19 to hold the lever 14 down until a new notch comesinto position above the nger 18. The spring 92 pressingupon the piston9| will force-the finger 18 into a notch as soon as the work carriagehas moved the correct distance to bring a cam opposite the grindingwheel. 'I'he work indexing motor is controlled by means of the valve 83.This valve consists of a bore in which a pair of spaced valve disksoperate, the disks being connected to a stemv 95 which projects out ofthe casing and is pivotally connected at 96 to a. lever 91. The lever 91is pivoted at 98 to the base of the machine and has one end pivoted tothe lower end of the valve stem 9|. Movement of the 75 valve stem 9|therefore, through the pivoted lever mechanism just described will movethe valve stem in the opposite direction. This controls the fluid portsas follows: When the valve 99 is in the position shown in Figures 6 and8 pressure fluid from the pump 93 is delivered through line |00 to thevalve chamber and through line |0| to the exhaust line 89. When thevalve stem 95 is moved to its uppermost position the valve disks willopen communication between pressure line |00 and pressure line |02 todeliver fluid to the reversing valve |03 into either port |04 or |05depending upon the position of the reverslng lever |06. When thereversing lever is to the right of the position shown' in Fig. 8pressure fluid will be delivered through the pipe |04 to the right ofthe piston 21 to move the work carriage to the left. The reversing lever|06 will be in position to the right of that shown in Figure 8 duringthe indexing operations on a shaft until the last cam has been groundand the machine has moved far enough to the left for a dog |01 on thework carriage to engage the reversing lever |06 to shift it to the left,but to stop it at the central or neutral position as shown in Figure 8to stop the carriage. To return the carriage to the right the operatormoves the lever |06 to the left at which time pressure fluid from theline |02 will pass through the line |05 to move the work carriage to theright in position for another series of grinding operations on a camshaft. As the work carriage returns to the right the dog |08 will movethe reversing lever |06 to its position as shown in Figure 8 to stopfurther movement of the work carriage. When the valve is in the positionshown in Figure 8 both sides of the cylinder are open to uid lines |04and |05 and hence to exhaust fluid line |09 so that the carriage isstopped and held in stationary position even though pressure fluid mightbe admitted to fluid line |02.

As best shown in Figure 7 there is provided a clutch throw-out mechanismconsisting of a bent lever ||0 pivoted at At the upper end of this leveris an inverted V-shaped cam block ||2 which is engageable by either oftwo cams, one at each end of the spacing bar 19. Only one cam 19 isshown. The opposite end of the lever acts through a pair of links |3 and4 to rotate an arm |5 which is pivoted at 6. 'I'he opposite end of thearm ||5 has a bifurcation to engage a spool ||9 to shift a clutch ||1 tostop rotation of the timing cam 54 and cam 55. A spring |8 acts normallyto hold the lever to keep the two parts of the clutch engaged.

The operation of the machine is as follows: Assuming that all partsofthe machine are in a, position to start grinding, i. e.,the master cam|9 and cam follower shoe 20 are engaged, the wheel base l2 is in rearposition and work carriage is at the right extreme of its travel. Theoperator places a cam shaft in the machine, the lever 14 is depressedbecause finger 18 is engaging the lower sideof the space bar 19 ratherthan one of the notches 80, the cam 19 on the spacing bar 19 is alsoengaged in holding the lever ||0 depressed to hold-the clutch ||1 ininoperative position. To start the machine the reversing lever |05 isthrown to the right causing pressure uid to enter the right hand end ofthe cylinder 28 and to move the piston 21 and carriage to the left. Assoon as the cam block 19' passes over the block ||2 it releases thelever ||0, the clutch ||1 is engaged and timing cams '54 and 55 begin torotate. The carriage continues to move to the left until finger 18enters the first notch 80. This allows the valves to return to normalposition in which pressure uid passes to cylinder 44 to cause master camI9 and roller 20`to become engaged and uid also passes 5 to the cylinder84 to move the wheel base |2 to grinding position. The valve 99 drops tonormal or lowermost position and at the same time bypasses pressurefluid to the reservoir instead of through the transverse cylinder. Thisstops the carriage in position to grind the rst cam. During the firstpart of the grinding operation cam 55 holds the switch 56 in openposition. In this position automatic switch 6| is open and circuitthrough 63 and 64 isbroken causing current to l5 pass through 62 and 69and the resistance 10. This gives a small amount of current through themotor field and thus causes the motor to operate at high speed. As soonas the roller begins to ride the low part of cam 55 the switch 56 isclosed, automatic switch 6| is closed and current passes through bothresistances 65 and 10 ln parallel, allowing a greater amount of currentto enter the field 61 and thus reduce the speed of the motor |1. Aftergrinding at a slow speed 25 for a predetermined time cam 54 lifts thelever 14, releases the carriage by withdrawing nger 18 from. the notch80 in the spacing bar 19, shifts the valves to again separate the mastercam and cam roller, withdraws grinding wheel 30 and traverses the workcarriage to the next cam. Then through roller shifting mechanismpreviously described roller 20 is shifted to position to engage themaster cam corresponding to the cam to be ground. After the last cam hasbeen ground 35 the carriage moves until the dog |01 engages thereversing lever |06 and shifts it to the central position, as shown inFigure 8thus stopping movement of the carriage.

It will be obvious to those skilled in the art 40 that various changesmay be made in our device without departing from the spirit of theinvention, and we, therefore, do not limit ourselves to what is shown inthe drawings and described in the specification, but only as set forthin the appended claims.

Having thus fully described our said invention, what we claim as new anddesire to secure by Letters Patent, is:

1. A machine for grinding cam shafts compris- 50 ing a base, a workcarriage, a grinding wheel, a. cradle swingably mounted on the Workcarriage, a master cam mounted on said cradle, a cam follower rolladapted to engage the master cam to swing the cradle, a motor forindexing the work 55 carriage past the grinding wheel, and meansoperated by said motor for shiftingthe camfollower shoe to position itadjacent a caml on the master cam shaft corresponding to cams on a workpiece which is being operated on by the 60 grinding wheel and a motoroperable independently of any moving parts on the machine for timingindexing of the work carriage, substantially as set forth.

2. In an automatic cam grinding machine having a work carriage, a wheelsupport and a work cradle, a fluid motor for operating said workcarriage and said wheel support, a timing and indexing mechanismcomprising a timing cam, a motor operable independently of othermechanism on the machine for driving said cam, a lever operated by saidcam, valves operable by said lever to operate the work carriage, Workcradle and wheel support, a notched spacing bar on the work carriage, afinger-on said lever adapted-to enter said notches, and means wherebysaid iinger may enter said notches without interference to stop the workcarriage in grinding position, substantially as set forth.

5 3. In an automatic cam grinding machine having a grinding wheelsupport and a grinding wheel mounted thereon, a work cradle and a workcarriage, pressure iiuid means for operating the work'carriage, wheelsupport and the work 105 cradle, a valve in control of said pressure uidmeans, a timing cam for controlling the operation of said valve, meansoperable independently of other mechanism on the machine for drivingsaid cam and automatic means to disconnect said cam and said drivingmeans at a predetermined point in the operation of the machine,substantially as set forth.

4. In a cam grinding machine, a work carriage, a grinding wheel, a workcradle pivoted on said 29.@ carriage, a motor driven timing cam, a motordriven independently of other mechanism on the machine for operatingsaid cam and` means operated by said timing cam to cause withdrawal ofthe wheel base and work cradle to inoperative po- 25., sition,substantially as set forth.

5. In a cam grinding machine having a base, a work carriage, a grindingwheel, a work cradle pivoted on said carriage, a timing cam, a motordrivenindependently of the mechanism on the gggmachine for operatingsaid cam, means operated by said timing cam to cause withdrawal of thewheel and work cradle to inoperative position the same means acting tocause a return of said wheel and said cradle to operative position,substantially las set forth.

6. An automatic cam grinding machine comprising a wheel base, a grindingwheel mounted thereon, a work carriage, a cradle pivotally mounted onsaid carriage, power means to operate v #said wheel base, carriage andcradle and a. timing and indexing mechanism for controlling theoperation of said power means, carriage and cradle, and a motor operableindependently of other mechanism on the machine for operating said-i-timing mechanism, substantially as set forth.

7. In a cam grinding machine, a bed, a wheel base, a work carriage, afluid motor for moving said work carriage transversely of said wheelbase,

a work supporting cradle pivotally mounted on said carriage, a spacingbar mounted on said carriage, a rotatable timing cam, means for lockingthe spacing bar in one of several predetermined positions, a valve incontrol of the carriage traverse motor and a lever actuated by the said-cam for releasing the locking means and for operating the said valvetocontrol movement of the wheel base and the work carriage, a motoroperable independently of other mechanism on the machine for operatingsaid cam, said spacing bar operating to hold said lever in depressedposition until said carriage has moved the work to another grindingposition.

8. In a cam grinding machine having a traverse said carriage accuratelyin several grinding positions, means to withdraw said locating meansfrom said bar at predetermined intervals, and meansactuated onwithdrawal of said locating means to actuate said carriage,substantially as set forth. 5

10. An automatic cam grinding machine comprising a traversable workcarriage, an oscillating work cradle on said carriage, a grinding wheel,a wheel support, means to provide relative traverse and longitudinalmovement between said carriage 10.; and said support, a spacing bar onsaid carriage having portions corresponding to several parts of a workpiece, means engaging said spacing bar and adapted to cooperate withsaid portions, and means actuated on withdrawal of said engaging 15'means to actua-te said carriage and to withdraw said wheel support androck said work cradle to inoperative position, substantially as setforth.

11. An automatic cam grinding machine having a work support, indexmechanism for said sup- 29; port, a grinding wheel, a support for saidwheel, mechanism to move one of said supports transversely of theother," mechanism to move the other support longitudinally of thefirst-named supportI and means whereby the movements of said sup- 25.'-ports are controlled by said indexing mechanism.

12. An automatic cam grinding machine having a Work support, a wheelsupport, power means to move said supports relative' to each othertransversely, and power means to move said supports 30 relative to eachother longitudinally, and means to effect said movements atpredetermined intervals including a spacing bar mounted one one of saidsupports, and control mechanism cooperating with said spacing bar andcontrolling the 35 power means imparting longitudinal movement to saidsupports to stop said longitudinal movement, said control mechanismoperating at the sametime to cause said transverse movement to bring thewheel and work into grinding contact. 3v

13. An automatic cam grinding machine having a work carriage index andcontrol mechanism comprising a spacing bar on said carriage, meansengaging said spacing bar and adapted to locate `said carriageaccurately in several grinding posi- 45 tions, means to withdraw saidlocating means from said bar at predetermined intervals, and meansactuated on withdrawal of said locating means to actuate said carriageand means actuted on withdrawal of said locating, means to move 50 saidwheel support to inoperative position, substantially as set forth.

14. An automatic cam grinding machine having a work support, a wheelsupport, power means to move said supports. means to provide relativetransverse and longitudinal movement of said supports at predeterminedintervals comprising a spacing' bar mounted on one of said supports, anelement in control of said power means adapted to cooperate with saidspacing bar to stop said 00"- longitudinal movement, said element actingalso to permit movement of the said wheel support into grindingposition, and means actuated on withdrawal of said element to move saidwheel support to inoperative position, substantially as set forth.

15. An automatic grinding machine having a work support and a wheelsupport, power means to provide relativev tranverse and longitudinal",-movement between said supports, a spacing bar on one of said supports,notches on said spacing bar, a nger ladapted to engage said notches tolocate .various portions of a work piece in grinding position, meansoperating with said nger to actuate said power means, and a timingmechanism to actuate said linger, substantially as set forth.

16. An automatic grinding machine having a work support and a wheelsupport, power means to provide relative transverse and longitudinalmovement of said supports, a spacing bar on one of said supports, afinger adapted to engage said spacing bar, control means for said powermeans adapted to be actuated synchronously with said flnger, means toactuate said finger at predetermined intervals to permit movement ofsaid work support, said means acting also to cause moment of saidsupport, substantially as set for 17. An automatic grinding machinehaving a power driven work support and wheel support, control mechanismfor said supports comprising a spacing bar on one of said supports,means adapted to cooperate with said spacing bar to locate the supportaccurately in successive grinding positions, means to withdraw saidlocating means from said bar at predetermined intervals, means actuatedon withdrawal of said locating means to actuate said support, and meansto hold said locating means in withdrawn position until said support hasmoved to the next grinding position, substantially as set forth. i

18. An automatic grinding machine having power driven work support andwheel support, indexing and control mechanism for said supportscomprising a spacing bar on one of said supports, means adapted tocooperate with said spacing bar to locate the support accurately insuccessive grinding positions and to cause said other support to movetoward and away from said rst support, means to withdraw said locatingmeans from said bar at predetermined intervals, means actuated onwithdrawal of said locating means to move one of said supports toinoperative position and the other to the next grinding position, meanswhereby said locating means may return to normal position relative tosaid spacing bar, and means actuated by said locating means in normalposition to stop said part in grinding position and to return said otherpart to operative position, substantially as set forth.

19. A machine for grinding cam shafts comprising a bed, a work carriageand a wheel base mounted thereon, a grinding wheel rotatably mounted onthe wheel base, a work support movably mounted upon the work carriage, amaster cam mounted on said work support, a cam follower roll engageableby the master cam, a motor for moving the work carriage relative to thegrinding wheel, means for indexing the work carriage to lock it inpredetermined positions with respect to the grinding Wheel, meansoperated by movement of the said work carriage for shifting the camfollower roll axially of the master cam and a motor operatedindependently of the carriage drive motor for timing indexing of thesaid carriage, substantially as set forth.

20. In a grinding machine, a work carriage, power means for driving saidcarriage, means automatically operable to start and stop said powermeans at intervals comprising means to time the movement of thecarriage, means to positively lock the carriage in grinding position,and means actuated by said timing means to unlock said carriage andcause said power means to move'it to the next position, substantially asset forth.

21. In a grinding machine, a work carriage, a wheel carriage, powermeans to drive said work carriage, means automatically operable to startand stop said power means at intervals comprising means to time themovement of the work carriage, means for locking the carriage ingrinding position, means actuated by said timing 5 means for unlockingsaid carriage and permit it to be moved by said power means to the nextposition, and means controlled by movement of the work carriage forstopping said timing means, substantially as set forth.

22. In a machine for grinding selected por-4 tions of a work piece, awheel base, work carriage and work cradle, means to provide intermittentrelative longitudinal and transverse movements of said parts, comprisinga spacing bar, mechanism adapted to cooperate with said spacing bar tocontrol the movement of the work carriage, wheel base and work cradle,means actuated by said mechanism in normal position to prevent movementof the work carriage, and to cause said wheel base and work cradle tomove to operative position, and means on said spacing bar to hold saidmechanism out of normal position after the last portion of the workpiece has been ground, substantially as set forth.

23. In a cam grinding machine having a work carriage and a motor foroperating said work carriage, avalve in control of said motor,means forlocking the work carriage in any one of several predetermined positions,a timing cam for releasing said locking means, a work drive motor, meansfor slowing down said work drive motor at a predetermined time,operative connection between said timing cam .and said speed changemechanism, and means for varying the point at which the change in speedof the work rotating motor occurs, substantially as set forth.

24. In a cam grinding machine of the kind described, a work drive motor,a cam for timing the indexing of a work carriage, means operablyconnected to said timing means for changing from high speed to low speedwork drive, and means for changing the relative duration of fast andslow speed operation of the work drive motor, substantially as setforth.

25. A hydraulically operated cam grinding machine comprising a rotatablegrinding wheel,

a traversable table, a rock bar thereon rotatably supporting a camshaftin operative relation to the wheel, means including a set of master camsand a follower to rock the bar and determine the cam contour during thegrinding operation, a fluid pressure operated mechansm t( traverse thetable in either direction, a uid pressure operated mechanism to rocksaid bar and move the camshaft to an inoperative position, meansincluding a iiuid pressure operated mechanism to move the wheel towardsand from the work to grind the cams thereon, a uid pressure systemincluding a valve mechanism connected 30 to each of said iiuid pressureoperated mechanisms and operating to admit fluid successively theretowhereby to traverse the table and position the cam opposite the wheel,then to move the wheel and grind the cam, and thereafter g5 to lock thebar and move the cam away from the wheel, and a main control cam foractuating said valve mechanism to control the cycle of operations.

26. A hydraulically driven automatic cam grinding machine of the typecovered by claim 25 comprising a drive shaft to rotate the main controlcam and a clutch arranged to connect said cam with the drive shaft atthe start of the grinding cycle and to disconnect it therefrom at theend of the cycle after the camshaft has been ground.

27. A hydraulically driven automatic camshaft grinding machine of thetype covered by claim 25 comprising a clutch to rotate the main controlcam, and means actuated by the traversing movement of the table toconnect said clutch at the start of the cycle and to disconnect it atthe end of the cycle of operation,

28. A hydraulically driven cam grinding machine comprising a rotatablegrinding wheel, a traversely movable slide therefor, fluid pressuremeans to move said slide, a longitudinally movable Work supportingtable, fluid pressure means to traverse said table, a rock bar pivotallymounted on said table and arranged to support a camshaft for movementtoward and from the grinding wheel, fluid pressure mechanism tov rocksaid bar to an inoperative position so as to separate the grinding wheeland the camshaft during the traversing movement, a main control valvemechanism arranged to admit fluid successively to said fluid pressuremechanisms, a rotatable control carnwhich is arranged to actuate saidvalve mechanism to control the cycle of operation, and a clutchlarranged to automatically connect said cam with the drive shaft at thestart of the grinding cycle and to disconnect it therefrom at the end ofthc cycle after the camshaft has been ground.

29. A hydraulically driven z utomatic camshaft grinding machine of thetype :overed by claim 25 comprising a clutch to rotat, the main controlcam, and means including a iog mechanism on the table arranged toconnect said clutch at the start of the cycle, to disconnect the clutchduring the truing operation and at the end of the grinding cycle.

30. In a grinding machine the combination with a work table having worksupporting means thereon, a grinding Wheel, a spacing bar xed lof eachportion.

to said work table and having seats therein, locking means engageablewith said seats for stoping the table and holding it in fixed position,means controlled by the machine for releasing said locking means, aiiuid motor for operating said table, and means operable upon a releaseof said locking means for controlling pressure uid to said motor.

31. In a machine of the kind described, a. work support, means to mounta work piece rotatably 10 thereon, a wheel support, mechanism to effectrelative transverse movement of saidsupports, mechanism to effectrelative longitudinal movement of said supports intermittently to bringthe grinding wheel into grinding relation with different portions of thework piece, means for rotating said Work, and a control means thereforfor rotating the work at a roughening speed and automatically changingthe speed of rotation to a finishing speed during the grinding of eachportion.

32. In a machine of the kind described, a work support, means to mount aWork piece rotatably thereon, a wheel support, mechanism to effectrelative transverse movement of said supports, mechanism to effectrelative longitudinal movement of said supports, a timing mechanism forintermittently effecting longitudinal movement of said supports to bringsaid Wheel and a series of portions of the work piece into operative 3ogrinding relation, means for rotating said work, and a control meansoperated by said timing mechanism for rotating the work at a roughening,speed and automatically changing the speed of rotation to a finishingspeed during the grinding CONRAD L. OTI.

AMOS P. STEINER. HAROLD E. BALSIGER. EDGAR P. WINE.

